Unable to close file handle

Question

Hi all,
i am writing a tiff to jpeg converter and it works so far.
the only problem that i have is, that as long as my application is not closed, i can not modify the newly created jpg files (like renaming them or something)
as i have read in another thread, the problem is the usage of JAI.create. i am not sure how to change my code though. please help me ~
here is the portion of my code that does the conversion.
RenderedOp op = JAI.create("fileload", path);
JPEGEncodeParam encodeParam = new JPEGEncodeParam();
encodeParam.setQuality(0.8f);
ParameterBlock pbSave = new ParameterBlock();
pbSave.addSource(op);
pbSave.add(destFile).add("JPEG").add(encodeParam);
JAI.create("filestore", pbSave);

Answer 1

This is a bug that is supposedly fixed in JAI 1.1.3. I'm not sure if ever was fixed though.
Both the fileload and filestore operations open streams which are never closed until finalized (i.e. garbage collected). In the fileload case, the problem is do to the deferred loading nature of JAI where a RenderedOp is not loaded until a method is actually called on it. So the stream is kept around until then. In the filestore case, it's a genuine bug.
The workaround is to append the following to that code snippet of yours:
JAI.create("filestore",pbSave);
pbSave = null; op = null;
System.gc();The garbage collector will (hopefully) run, and finalize the streams. The close() method will subsequently be called on the streams within the finalize() method.